What’s New in Photon Counting CT?

September 19, 2026 · 6 articles · 6 research themes · covering September 12, 2026 – September 19, 2026

Overview

Across this week’s studies and review, photon-counting CT (PCCT/PCD-CT) emerges as a platform for more reliable quantitative imaging—spanning physics, dose, and multiple clinical domains. A phantom investigation shows that conventional scan parameters still matter for quantitative spectral outputs: tube voltage (kV) meaningfully affects virtual monoenergetic image (VMI) CT values and contrast-to-noise ratio, helping define kV choices that optimize quantitative performance for specific VMI energies. Complementing this, a narrative review consolidates the detector-physics rationale for clinical gains in head and neck imaging, emphasizing higher spatial resolution, reduced noise/metal artifacts, lower radiation and iodinated contrast needs, and improved spectral imaging for small structures.

Clinically, the theme of “precision with less dose” appears in lung imaging: a prospective study tests ultra-low-dose PCCT against same-session standard low-dose CT, evaluating quantitative airway and emphysema metrics while tracking image quality and lesion assessment. In cardiology, PCCT-based measurements are moving beyond anatomy toward function and risk stratification. For TAVI, time-resolved PCD-CT–derived hemodynamic metrics are assessed for predicting prosthetic valve dysfunction, aiming to improve triage when echocardiography is inconclusive. For atrial fibrillation, precisely quantified epicardial adipose tissue on PCCT is evaluated as a biomarker for recurrence after catheter ablation.

Finally, an otology-focused case series highlights a practical diagnostic benefit: in surgically confirmed otosclerosis, PCCT features (e.g., increased stapes footplate thickness and/or hypoattenuation) correlate with intraoperative findings and reduce missed diagnoses on initial radiology reports. Together, these papers suggest that PCCT’s advantages—better signal quality, spectral capabilities, and improved artifact handling—are translating into both more accurate detection and more actionable quantitative biomarkers.

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ENT/Temporal Bone Imaging with Photon-Counting CT (Otosclerosis/Stapes)

Photon-counting CT for preoperative assessment of stapes footplate fixation in otosclerosis.

This retrospective case series studied photon-counting CT (PCCT) imaging findings of surgically confirmed stapes footplate fixation in 18 patients with otosclerosis undergoing temporal bone PCCT (March 2023–December 2024). PCCT features such as increased stapes footplate thickness and/or hypoattenuation correlated with intraoperative findings, and the study assessed how often these findings were missed on initial radiology reports. The results support PCCT as a more reliable preoperative tool for detecting stapes fixation in otosclerosis and reducing diagnostic misses before surgery.

Arora M, Seyedsaadat SM, Breen JT et al. · European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery · (2026) · View on PubMed ↗

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Dose Reduction & Low-Dose Photon-Counting CT in Lung Imaging

Quantitative and qualitative lung parameters in photon-counting CT: comparison of ultra-low-dose with standard low-dose protocols.

This prospective study evaluated how ultra-low-dose (ULD) photon-counting CT (PCCT) affects quantitative and qualitative lung parameters compared with same-session standard low-dose (LD) chest CT in 101 patients. Automated quantitative CT (QCT) and two readers showed the impact of ULD on noise index, airway segmentation/wall percentage, emphysema index (EI), mean lung density (MLD), and Percentile15 (Perc15) on soft (Br36u) and lung (Bl64u) kernels, alongside image-quality and lesion assessment scores. Clinically, the findings inform whether ULD PCCT can preserve diagnostic performance for airway and emphysema quantification while further reducing radiation dose.

Kroschke J, Jungblut L, von Stackelberg O et al. · European radiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Cardiac CT Functional Assessment (TAVI/Valvular Dysfunction)

Photon-counting detector CT for prediction of valve dysfunction after transcatheter aortic valve implantation: Comparison with echocardiography.

This retrospective single-center study assessed whether hemodynamic parameters derived from time-resolved photon-counting detector CT (PCD-CT) can predict prosthetic valve dysfunction after transcatheter aortic valve implantation (TAVI), compared with echocardiography. After CT-based exclusion of cases with severe mitral regurgitation and measurement of systolic prosthetic valve orifice area to compute mean values, the study evaluated diagnostic accuracy of CT-derived functional metrics against echo. The work advances noninvasive, CT-based functional assessment of TAVI valve dysfunction, potentially improving triage when echocardiography is inconclusive.

Hyska S, Osoria-Velasquez J, Hagar MT et al. · Journal of cardiovascular computed tomography · (2026) · View on PubMed ↗ · Free PDF ↗

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Cardiac CT Biomarkers in Atrial Fibrillation (Epicardial Adipose Tissue)

Epicardial adipose tissue in paroxysmal and persistent atrial fibrillation ablation using photon counting CT and automated 3D atrial segmentation: The Prospective AFAT Study.

The Prospective AFAT Study prospectively quantified epicardial adipose tissue (EAT) using photon-counting CT (PCCT) with semiautomated 3D biatrial segmentation in 210 adults undergoing first-time catheter ablation for paroxysmal or persistent atrial fibrillation. The study tested associations between volumetric EAT measures and arrhythmia recurrence after ablation. Scientifically and clinically, it clarifies whether precisely measured EAT burden on PCCT can serve as a biomarker for post-ablation recurrence risk in AF.

Erhard N, Bahlke F, Prommersberger S et al. · Heart rhythm · (2026) · View on PubMed ↗ · Free PDF ↗

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Head & Neck Applications of Photon-Counting CT (Review)

Photon-counting CT in head and neck radiology: bridging detector physics and clinical applications.

This narrative review examined how photon-counting CT (PCCT) detector physics translates into clinical advantages in head and neck radiology. It highlights improvements such as higher spatial resolution, reduced noise and metal artifacts, lower radiation exposure, reduced iodinated contrast dose, and spectral imaging capabilities, with examples including better visualization of small vessels, ossicles, and cartilage for preoperative planning and postoperative assessment. The review supports PCCT as a platform for more precise head-and-neck imaging and workflow improvements compared with conventional energy-integrating CT.

Martín-Noguerol T, Escartín J, López-Úbeda P et al. · European radiology · (2026) · View on PubMed ↗

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Photon-Counting CT (PCCT/PCD-CT) Physics & Quantitative Spectral Imaging

Influence of X-ray Tube Voltage on Computed Tomography Values and Contrast-Noise Ratios in Virtual Monoenergetic Images in routine clinical Photon Counting Detector Computed Tomography: Does kV Still Matter?

This phantom-based study investigated how X-ray tube voltage (kV) influences computed tomography (CT) values and contrast-to-noise ratios in virtual monoenergetic images (VMIs) generated from routine clinical photon-counting detector CT (PCD-CT). Across multiple tissue types, VMI keV levels, phantom sizes, and kV settings, the authors quantified kV dependence of VMI CT values and identified kV settings that optimize contrast-to-noise ratio for a given VMI energy. The findings address whether kV still matters for quantitative spectral imaging in PCD-CT, which is important for standardizing quantitative measurements across scans.

Jeukens CRLPN, Pinckaers FME, Martens B et al. · Investigative radiology · (2026) · View on PubMed ↗ · Free PDF ↗

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Generated automatically on September 19, 2026. Covers PubMed articles published September 12, 2026 – September 19, 2026. Summaries are AI-generated; always consult the original publication for clinical or research decisions.